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  1. o I finally have some production models of the New dual adjustment bungee I designed. I think I am going to call this one the QWEEGLE. Sort of a combination of Quick Bungee and Double for Double adjustment. I know a lot of you use your own harness, which in a lot of instances is a modified Camel Back. Camel Backs are great because they provide hydration and give you a great place to hook a bungee cord up to. Well I have thought long and hard about now to improve the QWEEGEE bungee which allowed you to adjust the length of the bungee where it attached to the rod. The BOOMERANG bungee which I also invented allowed you to adjust the length of the bungee at the "D" ring. The big issue with the QWEEGEE, was that you could only detach the bungee at the "D" ring, so when you laid your detector down the bungee was lying in the dirt. There was no way to detach the bungee from the shaft of the detector. Also where the bungee snapped onto the "D" ring it was pretty clumsy to get it on and off. I wear gloves, and when you wear gloves, small pieces of plastic are hard to deal with. So here was my challenge. 1. Design a bungee that could be adjusted with at the "D" ring or where the bungee attached to the rod. 2. Design a bungee that could easily be detached from the detector. or the "D" ring. 3. Make the process of detaching the bungee really easy and effortless. 4. Provide an optional attachment ring that would be similar to a "D" ring but be more durable, easier to attach to, allow the user to stitch it onto their own harness, and not turn around in the webbing you use to attach it. Standard "D" rings, always manage to wiggle around in the webbing and end up looking just like this "D" running vertical instead of like a U where the curved part of the "D" stays at the bottom. First part: Easy on and off attachment snap that attaches to "D" ring. Nice and hefty and durable. A thumb tab, to allow you to remove the bungee from the adjustment groove using one hand. Second Picture: Adjustment groove in snap. Lift or lower your detector while the bungee is out of the adjustment groove to find the right length, give a slight tug down to seat the bungee in the groove and lock the bungee to a perfect length for detecting comfort. SHAFT ATTACHMENT ADJUSTMENT Point. Long non-slip strap that will accommodate all known detector shafts, even the Garret ATX Deep Seeker that has a rod the size of a baseball bat. • Easily attach or detach bungee by pulling the bungee in or out of the SLIDE SLOT. Picture 3 • Easily adjust the length of the bungee by lifting your detector up or down, and then tugging the bungee up into the adjustment groove when you find the proper length. Picture 4 • Use the shaft attachment point only as an attachment point, and don't use the adjustment feature. Simply put the loop at the end on the bungee onto the shaft attachment point. Then you can use the snap at the "D" ring to make adjustments Picture 5 PICTURE 3 PICTURE 4 PICTURE 5 Then we have the optional non-slip "O" ring that I designed . Supplied with a piece of webbing for you to attach to your favorite harness system. I designed all of these pieces. I had to have injection molds made (not cheap) and had the parts molded out of Nyglass, which is a darn near bulletproof material. That "O" ring is 2 1/4 inside diameter. A blind drunk monkey could attach the snap to this "O" ring without ever worrying about having to see it. So I would love to hear your input. I have just 10 from the first production run. The rest will be sent by boat. Only the plastic parts and the strap are being shipped, we assemble the parts with the bungee here in Henderson. Some things are OK to have made in China, but bungee cord is not one of them. We use a very expensive high quality marine grade bungee. Doc
    4 points
  2. I understand where you're coming from. Auto tracking systems can have their advantages for inexperienced operators, or, as you said in"variable ground". They also had disadvantages, at least in some of the earlier systems. Around the late 1990's, well known detector designer Dave Johnson designed the Lobo Super Trac for Tesoro, or Lobo ST as it's most widely known. It had a very good ground tracking/balance system which was great for beginners. It had a shortcoming though. The tracking system could not be locked to the current ground phase when a target was found. As the user would wiggle the coil back and forth to further analyze the signal, the GB system continued tracking. At times it could actually track out (eliminate) the target signal as bad ground. It could/can be mitigated by making wider sweeps of the coil to let the tracking system read the surrounding soil matrix and adjust to that and not read the target as bad ground. Fast forward a year or two. Mr. Johnson, now working for Whites Electronics was in the process of designing two widely popular models for them, the GMT and MXT. He obviously was aware of the shortcomings of the Lobo ST tracking system. He made one huge addition to the whites models, the ability to lock the current ground phase in the tracking system when the user had a potential target. Once locked, the operator can move the coil back and forth to analyze the target with no worry of it being "tracked out" as bad ground. He also added the option to manually ground balance, and the very nice Ground Grab system which at the push of a button adjusts the ground phase of the machine to the ground matrix under the coil, as the computer constantly monitors the ground phase conditions. A great bunch of options at the time! Mr. Johnson has gotten away from auto ground tracking/adjusting systems for the most part at First Texas now. Most of their current machines employ the "Ground Grab" system, or the Ground Grab, plus a manual option most are familiar with. The newer machines of most other brands employ a variety of the GB options including tracking which is quite common now. They seem to work well. I still have a fondness for the GMT's options which are now nearly two decades old. As to the GB2. It's another one of Dave Johnson's excellent designs, and an all-time classic. I don't think I'd change a thing with that one! Sorry for the long winded post.
    3 points
  3. I finally got my hands on an 800. I'm a thrifty kinda guy so I waited until the inventory built up and while I did I was using the 600 to become familiar. Traded the 600 when I was done with it for an AT Pro, 3 AT coils, and Z-Link system plus $200. I played around with the AT Pro for 2 weeks before selling it for more than enough to buy a used, complete 800 for $700. I'll be honest with you guys. I've used a lot of machines, including an AT Pro before I had this AT Pro. I had the first one briefly with the big Nel 14" coil. It didn't leave an impression on me the first time. It did this time. This time I saw what all the fuss was about. It was a really fun machine to use. Very well behaved, but plenty deep, and I found a lot of nice things with it in that short time. I hated to give it up. But I digress. In any event, now that I have the fully loaded Equinox 800 and the V3i I'm gearing up to put on a very detailed head to head comparison. I like things very structured, scientific, and complete. One area I already see a blowout coming is the Equinox recovery speed quite noticeably outpaces the V3i. But there will be areas I expect the V3i to shine. With either one you get a lot of detector and I'm pretty satisfied that they can handle most any scenario I'm going to run into, especially now that I'm starting to put together a pretty good coil lineup for the V3i. If anyone has any specific areas of comparison you'd like to see, feel free to offer suggestions.
    3 points
  4. Thanks, I came to thinking/wishing they would sort out the ground issues when I was testing my coils and someone posted about how far their machine could air test a coke can, Well the coke cans over here are smaller at 330mils and when I did his test I Dare not publish my results because it would of started a war, even more so when I used my favourite coil, But I thought if I could get that depth then I would need a JCB and leave the pick at home, As it is I have a coil that can see Cans at up to 3 feet and maybe a bit more in the ground but it Air Tests at ridiculous distances, I have always thought if I loose 70% of that distance in the ground then I am still going to be digging 2 or 3 feet holes on a coke can, Perish the thought ?. Good ground balancing is one thing and the MXT has the best GB ever made but that is only a small part of the story because as we know the ground minerals can just destroy a detectors depth, but regardless of the GB system until a detector can wipe out those mineral then we are not going to see any improvements in depth, Because they have the same effect as Headlights in the Fog and when it gets too bad we have to turn down the gain so it can see, A bit like switching from High beam to low beam in the fog, We have detectors with multi frequencies that can ID a coin in a bucket of Nails with maga sweep speed and even faster separation speeds yet we still don't have a VLF that can see through the Mineral Soup that we face on a daily bases. We have everything but the Ability to see whats down there.
    3 points
  5. What a world of difference of the level of service in the new Pa. location from Florida.I was having s lot of static and signal breakup on the wireless Avantree phones I had for my 600.I first thought it was the phones but alter testing a second pair it was clear it was the machine.Contacted the service center and they sent me a shipping label for UPS so it was no cost to me.I sent it in on a Wed. and they had it on the bench on Friday,They could not find the issue at first,so Jamie went out a got a pair of non-minelab phones and had the same issue I had.He replaced the control pod and I had it back the next Wed. .The difference from when I sent my CTX to Florida was night and day.What a great change for the better!!
    2 points
  6. Thats the unfortunate reality of the internet. It’s soeasy for people to post vids and forum posts of things they perceive as problematic before they have taken the time to really learn the machine’s character and capabilities.
    2 points
  7. Happa -- I agree with Chase on the buried coins -- which will also help to see if you might have a faulty machine. I doubt you do, though; but, some testing might be in order. MEANWHILE, I would DEFINITELY make it a priority for a little while to go back to what you used to do, and "compare signals." YES, your Safari vs. their E-Tracs and Explorers would have given similar tones on a buried target, when comparing signals in the past -- but, that's why I think comparing signals now, with their FBS compared to your Equinox, would be so immensely helpful. YES, the sounds are different on FBS vs. Multi-IQ, but you would be comparing a "known" (FBS sounds on a deep coin) with an "unknown" (Equinox sounds on a deep coin), which should really, really help you to learn the "unknown." In other words, if they locate a deep, likely-to-be-wheatie target, and call you over to listen, you can listen with THEIR machine, first (and you'll of course recognize the target's sounds given your prior experience with FBS), and then, work the target with your Equinox, and listen closely to how the machine behaves. This will help you to figure out in your mind "what sounds like THIS on an FBS machine sounds like THIS on the Equinox." Yes, I have dug deep wheats that are down into the zinc range, and the same with deep Indians. So, you could be passing over some. They also sound much more subtle, at depth, than a shallow penny sounds. I at times will even get some occasional high-tone chirps mixed in, from certain angles, on a deep wheatie or deep Indian -- i.e. much higher than what you'd expect for a penny. Bottom line, burying targets at different depths and working them with your Equinox, and ESPECIALLY "comparing targets" with your FBS hunting partners, should move you quite a bit closer to having success with your Equinox. Don't lose confidence; I promise you that the Equinox (at least, one set up properly and working properly) will find coins every bit as deep as your buddies' FBS units, in most types of ground (including everywhere I've hunted). And for what it's worth, my machine of choice for many years was an Explorer, and I run a CTX now alongside my Equinox...and so when I say the Equinox is every bit as deep as FBS, it's a statement I feel confident in stating after through testing and experience with both Multi-IQ AND FBS. Steve
    2 points
  8. Overall Rating: 4.5 out of 5 Big Upgrade vs. AT Pro: Short Answer - YES!. The Garrett AT series is a solid detector series. The AT pro brought pro features, including a completely waterproof detector, high reliability and stable operation to the mid price range and it is no wonder it became so popular but it is getting a little long in the tooth, never had stellar ergonomics, and is now falling behind feature wise with its competition and with the release of the value priced Equinox and Kruzer series detectors, can no longer claim the high feature to price ratio crown that kept it a best seller for years. The AT Max added some bells and whistles (built in wireless, slightly improved ergonomics) and upped detector gain to placate the "depth is everything" crowd to its detriment (it appears to now be a mixed bag from a stability standpoint - be careful what you wish for, folks). The Equinox vs. AT Pro: Waterproof: Both are fully submersible up to 3M. Tie. Ergonomics - Equinox is not the best machine ergonomically speaking (the First Texas F75/T2 machines retain that crown IMHO), but it is definitely better than the AT Pro. Lighter, better balanced (though still nose heavy), much easier display to read, and intuitive menu navigation vs. AT Pro. Backlit display a plus on Equinox. Prize goes to Equinox. Wet Salt Beach Performance: Multi IQ multifrequency operation enables superior stability even at high gain settings vs. AT Pro on wet sand. Depth: Deep as any machine I have used. I have not been limited by its detection depth so far in any situation, except unusually highly mineralized soil conditions where no VLF machine performs well (most people use Pulse Induction machines in this particular relic hunting situation). Recovery Speed: Variable recovery speed settings enable the Equinox to be used in a variety of site conditions from a very trashy home site, where you can separate the keepers from the junk to deep silver seeking in a relatively pristine park. AT Pro recovery speed is decent but fixed so separation in high trash environments suffers even with the smaller "sniper" third party coils. Multi IQ vs. Single Frequency - Multiple Multi IQ profiles enable the Equinox to be optimized for specific targets such as high conductive silver, small jewelry, gold nuggets, mid-conductive relic buttons, deep nickels. It is like having a multiple machines in one package that enables you to tackle a variety of detecting situations. The AT series has even fallen behind discrete "single frequency" machines at similar price points like the Nokta Impact and Makro Kruzer that enable multiple different individual frequencies to be selected one at a time depending on the targets of interest (low frequencies for high conductors like silver or mid frequencies for all around detecting and high frequencies for mid-conductive targets like gold jewelry and relics). Equinox takes that to the next level by enabling the multiple frequencies to be transmitted SIMULTANEIOUSLY which enables stable target ID acquisition, precise, yet forgiving ground balancing, enables signal processing filters mitigate iron falsing, and gives the stable salt beach operation I described previously. It is like having the AT Pro and AT Gold plus a higher frequency gold machine all wrapped up in one machine. Equinox wins this one. Third Party Coil Support: Right now, ML has only announced three coils for the Equinox, two are now available (the stock 11" DD and a 6" round DD), with a larger 15 x13" elliptical open coil being available soon. AT Pro has been around long enough to have a number of third party coil manufacturers make a variety of coils beyond the Garrett OEM coil lineup. So at this time the edge goes to AT Pro, but this will not last long. High praise so far for the stock Equinox coil and 6" coil, and the third large coil should have 90% of the bases covered. User Settings and Future Upgradeability: First of all the default user settings work great out of the box. So, it is a great turn on and go detector. You simply, choose the search profile desired, let the Auto EMI noise cancel choose the quietest detecting channel, ground balance as necessary, and start swinging. With all the built in search profiles you can explore different areas of detecting you might not have thought about because of the limitations of your current machine (like gold prospecting, or relic hunting in highly mineralized soil). But you have the flexibility of exploring and adjusting advanced settings and customizing the tone settings to your liking. Finally, the Equinox has a connection that enables you to upload future firmware updates that either fix bugs or that may allow future performance enhancements. Other than adding accessory coils, you will not squeeze much more out of the AT pro as it ages in your detecting arsenal. Rechargeable Battery: The battery lasts a long time (at least 12 hours continuous detecting), is user replaceable, (should last 3 to 5 years or more under normal usage), and charges quickly (fully charges within a couple of hours from "empty". You can even charge the battery on the go (i.e., while detecting) from a portable battery USB power source affixed to your detector shaft if you are so inclined. I know that there is something about the ability to pop in some AA batteries in a pinch, but I have never had this detector let me down because of a rechargeable battery problem. On an all day detecting run I have not gone below 2 bars. So if you forget to recharge your battery from the last detecting session, you likely will have more than enough juice for a couple 3 to 4 hour back-to-back hunts on separate days. Neutral on this as this is more of a personal preference thing because you can go back and forth for hours debating the merits of "built-in" rechargeable batteries that cannot be substituted with conventional batteries "if something goes wrong with the rechargeable". I prefer the Equinox rechargeable even though a few folks have reported battery or charging circuit failures. Built-In wireless audio using both readily available Bluetooth accessories you can buy from Amazon (800 includes a wireless headset) and also proprietary wireless receivers (included with the 800, into which you can plug your favorite headset). I could go on, but we would start getting into the weeds. What Do I Like Most: It's versatility. I have been able to get rid of a few "specialized" machines as a result of its ability to be a jack of all trades, and a near master of some (shallow water salt beach hunting, relic hunting in trashy plowed fields). What Do I like Least: The shaft design seems like an afterthought and seems to be a weak link although ML is honoring their warranty, the issues are relatively minor and can be addressed in various McGyverish ways (duct tape anyone?), don't manifest on every detector, and their are some great, superior third party shaft options out there which even if you spend the extra bucks to buy one of these still enables you to spend less overall than you might have on arguably less capable machines because of the excellent value pricing. Do I recommend it as an upgrade to your AT Pro? Yes. One last recommendation: Peruse this forum especially Steve's compilation of other Equinox info in the first sticky post and determine whether the Equinox 600 or 800 is the right choice for you. HTH
    2 points
  9. I have only detected with Steve twice at Crow Creek, but both times I made an amazing discovery. The first discovery I made was that you don't ever let Steve get in front of you, the ground will be sterilized after he passes through. The second discovery I made was that you don't ever let Steve get behind you, he's like a turkey on a June Bug. Anything you miss, which is everything for me, he will have it in an instant. In other words, you get it the first time or it is gone forever, no second chances.
    2 points
  10. Part III Gold As it turns out there is tiny -100 mesh gold just about anywhere you stick the shovel. In any pan you're likely to see 3 or 4 tiny specs of gold and a lot of black sand. The problem is as old as time, find a concentration and figure out a way to recover it. What I discovered on the gravel bar was a thin flood layer about 4 inches thick under about 8 inches of overburden. The layer was distinct because it contained mostly sharp cornered gravel rather than typical rounded river gravel and it contained a lot of mud/silt/clay binding the layer together. Once you get a decent hole started you can chase the layer, pushing the overburden in behind you. A typical pan of this material is likely to contain 30 to 50 colors, mostly -100 all the way down to -400. I had a pocket magnifier and looked at this stuff under 100x magnification. It's incredible, but you really have to get a lot of it to have any real weight. It really looks impressive when you have to black sand to highlight it, but when you pan off the black sand this stuff will float right out of the pan. I had reconfigured my Gold Cube to be more of stacked sluice, capable of handling 1/4 inch material. I added Deep V black matting to the top tray, one of the new esoteric "catch it all miracle" mats to the second tray and Deep V in the 3rd tray. The top tray was catching 90 percent of the gold, so I only cleaned the bottom trays at the end of the day. I would dig 2 buckets (4 half buckets for carrying ease) classified down to 1/4 inch then run it through the Cube. Photo 1 is what typically I would get out of 2 buckets. I would pan it down to the black sand and if there were any pickers I take them out and dump the concentrates into another bucket for later processing. After a couple days it was clear that this type of gold production wasn't going to change my lifestyle much. The most I ever ran was 10 buckets. After a few days I panned off the +50 mesh gold for 2.87 grams. Clearly I wasn't going to get rich on this project. But, it was better than being home in Yuma at 118 degrees. My girlfriend would occasionally get energetic and help shake the bucket classifier, but she was satisfied sitting in the shade reading. I figure I was getting about 1 gram of gold per day, working a couple hrs, then swimming, fishing etc. A more dedicated person with a sluice tuned for beach type gold could obviously do much better. After she left, I started exploring and sampling in more remote areas. A lot of hiking and the best I found was an area with all this riverside sedge grass growing right on the bedrock. It involved a rigorous hike on a very narrow trail overgrown with poison oak. I stuck to panning because I didn't want to haul much equipment in there. An unbalanced pack on that steep trail might have been disastrous. The roots of this sedge were like natural miner's moss. They were so tough I chopped them with a hatchet them shredded them up in a bucket of water. It might take an hr to get 1/4 bucket of this material, but it was so rich in fine gold. In photo #2 is the gold I took out of one pan from a crack under the sedge roots. Unfortunately, there just weren't many of those. The weather had turned really hot, so I would sit on a ledge waist deep in the water and pan out my 1/4 bucket. Again, I would pan down to the black sands then save it in a concentrate bucket. After I got tired of panning I would have to waste time until the sun set enough for the long hike back to my Rokon. Again, if I had been serious with the right equipment, I could probably get 3 or 4 grams a day until I ran out of sedge grass. So, after 3 weeks I decided to go get some big gold at Rye Patch, and we know how that turned out.
    2 points
  11. Part II Every year I devise some new scheme to get the gold out of that river. One year I even set up a gravity dredge with 60' of 4'' hose. It worked fine, but it really takes 2 people to manage it. If you get a blockage it's an absolute bear to drag that hose out, shake out the blockage, then get it all back in the water and re-charge the suction. This year I decided to just concentrate on the flood gold and work less hard. During the past winter I watched various You-Tube videos of the guys on the beaches trying to capture fly speck gold. I figured I could find a decent inside bend of the river and dig the easy stuff off the banks. My plan got a little further complicated when my girlfriend decided she would like to join me for 10 days on the river. Mind you, this is rough, dry camping. Since the BLM roadblock, the only camping space is an old helicopter landing area, over a mile from the river with no local water source, and certainly no toilet facilities. I traveled ahead by 4 days to set things up and she would fly into Sacramento. I set up a decent camp, stand up room tent with an inflatable queen bed. I had pre-positioned bear spray easily accessible under the awning and in the tent, just in case. I set up a potty area with one of those toilet seats you put on a 5 gallon bucket. I bought the potty bags that help keep the mess in order for later disposal. I found a decent gravel bar with about a half mile walk from where I could park the Rokon, cleared the trail of poison oak and set up a portable shade and a chair on the gravel bar. The only real hazard was a steep section of trail with about a 50' drop, with the trail littered with dry oak leaves. They can be like stepping on roller skates in that kind of terrain, but I did the best I could. She arrived and on the drive down the nasty washed out road she started to wonder what she had gotten herself into, but she was game and soldiered on. I pointed out the poison oak all around the camp and cautioned repeatedly, "don't leave the trail". So it was for the next 10 days. We rode double on the Rokon and only crashed 4 times, all at low speed and generally into the blackberry bushes. No major injuries, minor scrapes, bruises and stickers. The hike proved to be a challenge, particularly the nasty 50' steep section. She developed a pattern of places to stop and catch her breath and take a drink of water. She likes to think she works out at the gym, but this was a bit different. I kept telling her, "it's the cardio", you'll get used to it. She didn't weigh 130 lbs soaking wet when we started, but managed to lose 7 lbs in the 10 days on the river. In the river I had a net bag of beer, soda and water. I carried fresh snacks down everyday so it really was paradise, kind of. I would drive the Rokon down to the spring every evening and fill up a 5 gallon tote bag of water for bathing. I'd heat up enough and fill a bucket with warm water. We used a gatorade bottle with the top cut off as a scoop to pour water for our shower. The bear only visited once. I carelessly left the trash out and there he was. I scared him off and didn't have to use the bear spray. At the end of 10 days, my girlfriend had to fly home reluctantly. In Part III, I'll talk about the gold....
    2 points
  12. The secret to the Minelab GPX series is thoroughly understanding the timings and when to use each one. Timings are variations of the basic pulse induction technology at work in the GPX series that gives you far more flexibility than exists in other pulse induction detectors. Unfortunately this extra flexibility also adds complexity, and so it is not unusual that some people may not be using the optimum settings in many cases. It is very important when investing in a Minelab GPX detector to take the time to read the manuals and study until you fully understand what the settings do and how to adjust the detector for the best performance. Otherwise you will not be getting all the potential out of your investment. The chart below shows the timings and what GPX models they are available on along with a general description. The descriptions are from the owners manuals that are available by download at the bottom of the page. In general you should always use timings as near the top of the chart as possible, with the exception of the Salt settings. Those are for alkali flat and salt water beach areas only. Using timings designed for more mineralization than is actually required may result in less depth on desired targets. Imagine the timings as another sort of ground balance setting. Low mineral settings are more powerful than high mineral settings and should be used whenever possible. Some confusion is the result of the timing names. Some people assume the Fine Gold timing is best for fine gold. This does make a sort of sense, but the fact is Fine Gold is just better than other high mineralization timings on smaller gold. In milder ground Sensitive Extra will obtain better results on small shallow gold. It is also very important to know that some timings work better with one coil type or the other. Minelab GPX Timings Chart Little or No Mineralization Coin/Relic (GPX 4800, 5000 ONLY) Coin/Relic is for use in lightly mineralized soils including many beaches and loamy soils. It offers maximum detection depth on a range of target sizes, significantly greater than any other timings. However, if the ground is any more than lightly mineralized, the detector may not ground balance properly. On ocean beaches containing significant quantities of black sand, better results may be had by using Normal or Salt settings. Mild Mineralization Sharp (GPX 4500, 4800, 5000) Sharp is similar to Normal but creates a more powerful detection field. It is capable of an improvement in depth, but is more susceptible to interference and will increase the severity of false signals in difficult grounds. This timing is best used in quiet conditions and can work well in combination with Deep Search Mode with a reduced Rx Gain setting. Sharp is an excellent tool for pinpointing faint signals due to the very "sharp" signal response. Sharp will work best with DD coils in most gold field locations. Medium Low Mineralization Sensitive Extra (GPX 4000, 4500, 4800, 5000) This timing may increase the signal from certain hot rocks near the surface, but can actually help smooth out the Threshold in certain ground types, particularly with Double-D coils. In mild ground conditions Sensitive Extra will provide the best signal response on a small, deep target. Medium Mineralization Normal (GPX 4000, 4500, 4800, 5000) Normal gives you the best performance on a wide range of soil conditions, and it will provide the best depth on a wide variety of target sizes. It works particularly well with the supplied 11" DD search coil for general detecting. You should always use Normal in new areas where you are unsure of the soil mineralization and the depth of targets. Medium High Mineralization Salt Coarse (GPX 4000, 4500, 4800) The effect of alkaline salt mineralization is vastly different to the effect of ironstone and mineralized clays. Normal should be tried first in these areas, but if the Threshold is too unstable then better performance will be obtained in Salt-Coarse. Using the Salt-Coarse timing may result in a loss in signal response to smaller targets. However, the response on larger items remains relatively unaffected and ground noise is usually minimized. Medium High Mineralization Salt/Gold (GPX 5000 ONLY) Provides the best signal response on small to large gold in salt saturated and mineralized ground conditions. It should work well on dry inland salt lakes, high salt concentrated goldfields, and mineralized saltwater beaches. Extremely salt saturated soils may still need to be searched with the coil switch in Cancel (using a Double D coil). High Mineralization Fine Gold (GPX 5000 ONLY) Fine Gold is sensitive to smaller targets in highly mineralized ground. It provides a sharper signal on small gold compared to Enhance, and improves the detectability of rough/flaky gold and specimens, while ignoring most hot rock signals and false ground noises. Shallow, highly mineralized ground where gold has been found previously should be re-examined with Fine Gold, and best results will be had by using the optional 8” and 11” Commander Monoloop coils. Note: Sensitive Extra will provide superior results on small gold in milder ground. Very High Mineralization Enhance (GPX 4500, 4800, Improved in GPX 5000) Runs quietly in most heavily mineralized, variable and "hot rock" infested grounds using a monoloop coil. It is more sensitive and detects deeper than Sensitive Smooth but can be slightly more affected by severe ground mineralization. Severe Mineralization Sensitive Smooth (GPX 4000, 4500, 5000) Sensitive Smooth is optimized for an improved response on smaller, shallow nuggets in severe soils. There is a loss of depth on bigger targets; so you should not use this setting when seeking out large, deep nuggets. Sensitive Smooth is best suited for use with monoloop coils in difficult soils. It eliminates most false signals from hot rocks, and ground mineralization, whilst retaining excellent sensitivity to small targets. The example below shows three common timings and where they should be used. It also highlights why using the wrong timing for the conditions can result in missed targets. Minelab Mineralization and Timing Example The following chart illustrates the procedure for finding the correct timing for each situation. In general, always start with the Normal timing. If the detector is stable and quiet, try timings on the left - Sensitive Extra, Sharp, or in rare cases, Coin/Relic. If ground noise or hot rocks present problems in Normal, then try timings on the right - Fine Gold, Enhance, or Sensitive Smooth. Salt settings should generally only be used on alkali ground (salt flats) or salt water beaches, but may have applications in other ground. The goal is always to find the most powerful setting that allows for stable operation. Each timing can be adjusted within certain parameters, primarily through the use of the Gain and Stabilizer settings. Adjusting for a lower Gain, for example, may be preferable to going to a less powerful timing. Minelab GPX Timing Selection Chart - Click on image for larger version Finally, each timing may work best with a certain type of coil (DD or Mono) and the timings have varying level of resistance to Electro Magnetic Interference (EMI). The matrix below attempts to show which timings offers which benefits and strengths/weaknesses. Minelab Timing Coil EMI Matrix - Click on image for larger version The simple chart below can be printed out and taped or glued on your detector shaft as a reminder in the field as to which timing may be best. Click on the image to download a large version. Minelab Timing Decal - Click on image for larger version Minelab GPX 4800/5000 Instruction Manual Download Here Minelab GPX Series Quick Start Guide Download Here Beginner's Guide to Tuning the Minelab GPX 5000 Minelab GPX 4800/5000 Product Brochure Download Here Minelab Commander Coil Brochure Download Here Minelab GPX 4500 Instruction Manual Download Here Minelab GPX 4000 Instruction Manual Download Here ~ Steve Herschbach Copyright © 2011 Herschbach Enterprises
    1 point
  13. The River I spent several weeks in early July, panning and sluicing on the N. Fork of the American River. I've been going to the same 10 mile section of the river for over 20 yrs. That part of the river is designated Wild & Scenic, so no motorized equipment and no claims. It's one of the few places in CA gold country you can access a free flowing river without stepping on someone's gold claim. Access is not easy, although there a a number of trails up and down the river. They're all rugged, often steep and always overgrown with poison oak. I have often encountered "locals" who at various times attempt to eke out an existence by panning and sluicing the river. Generally friendly and sometimes willing to share local knowledge of the gold. When I meet them I make a point to brew up a big pot of spaghetti and feed all comers. Many years ago, I met a guy my age driving a new Jeep Cherokee. He was socially awkward, but I learned he was a software engineer from the Silicon Valley and had taken up gold prospecting on weekends. He was not very successful, so my 6 yr old son and I invited him to come dig in a hole we had started. He sluiced a few buckets and declared that was more gold than he had ever found. Skip ahead 10 years, I found him living in a tent on the banks of the river having spent 2 years pursuing the golden dream. He was eking out an existence and seemed to be perfectly happy. Imagine a 6 mile hike uphill, just to reach a paved road, hope for a ride to town to get supplies then repeat the process back down. Supplies are limited to what you can afford and carry on your back. The local mining supply store pays 80 percent of spot, for good clean gold. This guy still had the math and engineering brain so he could tell me exactly how much he was earning per hr, although he did not factor that it was in fact a 24 hr a day job, living on the river. Every now and then "flatlanders" discover the place and bring down a bunch of gear intending to strike it rich. They are soon disillusioned and I find their gear stashed in the woods. I've seen one sleeping bag stashed in the same spot for over 4 years, untouched. Buckets and digging tools get carried away by spring floods and I find them littered on gravel bars. Access There is an old mining road ,overgrown, heavily rutted, washed out and frequently blocked by blown down timber. It currently takes me about an hr to travel just over 3 miles down that road crawling in 4 wheel drive low locked in 1st gear. At one time you could drive to within 100 yds of the river. There was a fabulous camping spot under a massive oak, with a spring nearby. In their infinite wisdom, the BLM blocked the road about 1.5 miles from the old camping spot. They brought in some heavy equipment and dug tank traps to block all future traffic down the road. For many seasons I hiked the rest of the way down on a variety of trails. A few yrs ago, my son, then strapping teenager and I started hacking an ATV trail around the tank traps. We spent a few hrs a day for over a week cutting a new trail. It's passable by ATV to this day, but you really have to know the danger spots or slide right down the hill. I've winched my own ATV up that zone many times. More to come in Part II.....
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  14. Yep he is a fast learner and he has all the right gear so success is just around the corner. the recent influx of LF machines has opened a lot of peoples eyes that were once blinkered by PI machines, finally people are taking note, they seem to forget that the biggest nugget ever found with a detector was found with a VLF in the GT in a time before PI's were invented, Since then Recovery speed has got better so has Disc and ground balance systems work in all but the most extreme conditions, Not to mention that even big Coils are a lot hotter than the little ones we use to use back in the 80's. My largest coils can see bits down to 0.02 on the surface. Even though I prefer VLF's I like searching hot ground because I can get the detector running right on the edge and a few things happen that either people don't know or they just ignore but in shallow ground and junk sites these LF machines really come in to their own.
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  15. You can cheat with an auto tracking machine if you want to up the GB a bit by ground balancing but only lowering you Coil down to 4 or 5 inches off the ground or even higher and you can make it go the other way by only raising it by about 3 inches from the ground and by letting the coil linger on the ground, So you can off set the GB to suit although you have little control by how much, I know with one pump of the coil it will be slightly negative and at two pumps it will be slightly positive and by the third pump it will be more so making a bit more noise as you lower the coil, but as a rule it always ground balances with 2 pumps of the coil or if I have had the tracking locked If I press and release the ground grab it update to the current GB setting that the detector see's without have to pump the coil and it only takes about half a second or less for it to GB it's self, Manual GB is handy for those who like to tweak things but if you only have Auto track and Lock you can imitate it to a fair degree.
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  16. Thanx guys... I plan on working out and testing with your suggestions. I'm loving the simplicity and detecting options of this machine and I want to get everything I can out of it. I'll report back. As always good luck and happy hunting !!!
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  17. another great design, Doc...unfortunately, I have yet to wear-out the ones I bought years ago. I would not be without your bungee and Chris' Hipstik on my GPZ... thanks for being an inventor. fred
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  18. The depth difference will depend on the level of mineralization. The TDI is a ground balancing PI, the Surf Dual is not. If you have low mineral soil (Florida) then no reason to get excited by this new model. West coast, Hawaii and other volcanic islands, that is where ground balance will give you a depth edge and help with hot rocks.
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  19. No GB it is the Detech Excelerator EQ2 Pro 14x10, I have one on the machine and a brand new one still in it's box as a spare. This is It, https://www.ebay.co.uk/itm/DETECH-14-x-10-DD-Elliptical-COIL-for-Whites-DFX-MXT-Series-M6-and-MX5/273363022240?hash=item3fa5b4b1a0:g:5bEAAOSwQz1bKBgR
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  20. Published on Jul 29, 2012 - How to find gold with the Whites GMT. Gerry shows the settings and techniques for finding even the smallest nuggets.
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  21. I was lucky enough to find a couple large cents awhile back and was hoping someone knowledgeable with copper coins / large cents could shed some light on dating one of them. The 1845 large cent (good condition) measures appx. 27mm while the other large cent (which is in extremely poor condition) measures appx. 28mm. The larger coin also has the word "CENT" underlined on the reverse whereas the 1845 does not (see photos). I have The Official Red Book of United States Coins, 63rd edition (2010) and I believe the larger cent is older. Anyone have an opinion on appx. date of larger cent?  Thanks in advance, Malcolm
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  22. Those are really good settings for deep silver and copper. I don't know what to tell you but try putting some into the ground at depth in a test garden and see what they sound like shallow vs. deep and in various modes including single frequency. Even pure non-ferrous targets can give a ferrous grunt (when in AM) off the edge. Give AM a try if you are not already doing so (you can turn down the ferrous volume) to see if that enables the high conductors to stand out.
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  23. I have had many detectors that could coin, relic, jewelry, and nugget hunt well, but then had to have another detector for saltwater detecting. Now I can nugget detect one day and hunt in saltwater the next. There is no other detector I am aware of that can do so many different metal detecting tasks and do them all not just well, but in many cases better than machines dedicated to those tasks. Multi-IQ is very powerful. Main dislikes? Handle grip is a little large for my hands, wish it had a 6" x 10" fully enclosed coil, expanded target id spread would be nice.
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  24. It's not just you, that is the world we live in now, $1000 for an Iphone and they bring out a new one 6 months later, and the new comers to the hobby who work for these companies are trying to do the same to detecting and we have had quite a few machines put on the market that are less than Inspiring even on a good day, I would much rather they spent a couple of years getting it right than blow my hard earned cash and regret it a week later as we have seen in the past,
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  25. Well looking at as an observer from the out side looking in, Back when the MXT,GMT and the GB II were made field testers and engineers us to work hard together and would not release the machine until it was All it could be, but around 2010 that all changed and machines have been released when near enough is good enough and if there is any problems they will put it right at the Owners inconvenience As we have seen this a lot in the past couple of years with some machines going back 3-4-and 5 times, that sours on lookers and drives people away, And although these 3 machines are old tech they can still run with the pack. The trouble with machines that are phased out within 2 years means that if there is a problem they won't work on a fix for everyone but they will fix individual machines as they go wrong, They came up with the Idea of the MXT in Late 1998 when work first started and it was released in mid 2002, people wonder why they are so good well that's what you get when the best Engineers and Prospectors combine resources and work together for over 3 and a 1/2 years to make sure it's all it can be, And 16 years later they are still good, The future of VLFs will not make any huge leaps but instead of major depth increases what we will see is smarter detectors that can unravel the ground noise and allow the machine to send and receive its signals hopefully in the same sort of ranges as they Air test because If they could only get that signal to go in the ground and return a signal then they would match a PI 90% of the time, I would say that the VLF technology has not reached it's peak but I would say it is in a state of confusion where it has stalled and if they can unravel the Gremlin that stops a VLF from putting it's power in to the ground then the person/company who does that will make billions, We don't need better coils or more power, what we need is the power we have but be able to get it in the ground in all conditions not just mild to medium high soils, Do that and you would have a GPZ with the Disc of the MXT and you would be unstoppable.
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  26. Nice going Stephen, great looking gold. Sounds like there wont be much training going on, just finding nuggets :) Brian.
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  27. for finding the class ring but this mornings hunt produced this ticket in the first 1/2 hour. 8.9 grams marked au585 ?
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  28. Well the guy that made the first video I was watching has made a second one. It started off with him doing a comparison of a At Pro and the Makro Multi Kruzer on different targets at depth. He said he was running the MMK in three tones doing the test this time. He went from one two the other as his testing went with the MMK hitting the target and not always with the AT Pro. As time went by he didn’t pickup the Pro anymore and didn’t put the MMK down anymore. He was the same one in his other video that was saying how much it chatter in 4 tones plus loss depth in 3 tones. Here he was making finds that he never could before with other Detectors. Maybe next time he’ll put brain in gear before putting mouth in motion. Chuck
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  29. Welcome to the forum! So do you want a high frequency VLF that is hot on small gold or do you not? “Too sensitive” is the name of the game. From my perspective all over 30 kHz units are roughly equivalent and all are edgy machines. I can find gold about as well with any of them. If you are looking for head to head testing that proves any one of them to be significantly better than the others - good luck with that. Whether it is a twenty year old Gold Bug 2 or the latest hot new machine, dealing with ground issues, hot rocks, and chatter is just the way it is. None of them is a magic bullet. Once I get my hands on the new Goldmaster 24K I am thinking this flood of new high frequency nugget detectors will pause for some time. That being the case I am going to do a more in depth critical comparison of all the models then I have ever attempted before. But that will be more towards the end of the year as I need time to round up a 24K and get good with it first. Covers make them all rain proof but if you think that the detector itself being rainproof is important than the Gold Kruzer and Gold Monster do have that. The Monster can be run totally automatic and can run silent if you want to give up that noisy edge. Though so can the Gold Bug 2 for that matter if tuned properly. The Gold Kruzer has far more control options and is more kin to the Gold Bug 2 than the Gold Monster. I found I liked the Gold Monster more than I thought I would given the lack of control options. However, my own personal tastes are for detectors with more control, not less, so units like the Gold Kruzer ultimately appeal more to me. If ground balancing and hot rocks trouble you, and price is no object, the Minelab SDC 2300 is a great PI option. Related thread Which Nugget Detector?
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  30. There is lots of info on the internet that can be found quite easily with a little searching. Try "Wiki US Large Cents" and you will get plenty of info. The more corroded one seems to be a "matron head" type (1816 to 1839). The better on of the two seems to be a braided hair type.
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  31. Hi all, had a half day to go detecting today, so I went back to that new patch and was able to find one more small rough nugget. Searched a lot tried to expand the area or find source but no luck. So I want of searching for a new area, looking on a hillside next to a wash where I found a few nuggets. No luck, but I did notice a steep wash up ahead that I couldn't remember detecting. Found some nuggets nearby so I figured it was worth it. Ended up finding 4 more nuggets in a new patch. All small, but way better than a skunk. The darker nugget was from last weeks patch. Chris
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  32. Good data collection&measurement. I'm looking at my Redbook (54th ed., 2001) and it seems to indicate that the larger diameter version (Designer Robert Scott) was minted prior to 1837. Those dated 1837 and later were designed by Christian Gobrecht and termed 'Young Head'. For the pre-1837 type there were two versions of lettering on the reverse (again from my Redbook). IMO (and it's very difficult to discern so don't put too much stock in my view) yours is the 1829-1837 variety. For the Scott design there seems to be a variation on the head profile on the obverse: 'Matron head' being minted 1816 to 1835. So that also can narrow down the date range of your coin, but it will take someone much more expert than I to figure this part out. Regardless, you've made some nice finds. And good for you to try an figure out more than meets the untrained eye.
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  33. I mostly dig the iron foolers unless they are large or deep (with a fainter dragged out tone) then I pass. It doesn't matter to me if negative numbers show, that is if I am actually watching the meter during the process, or there are iron tones mixed in I dig based on consistency of tone when the target is well centered under the coil. Like TNSS said it's also my experience that deeper targets can have faint iron sounds mixed in but still give a consistent overall tone and TID reading at some point in off angles of approach when centered. As he said it could be the ground itself or migrated iron from well rotted iron objects causing this. If approached with good coil control the Nox is very consistent on borderline targets. In fact, the word "iffy" almost doesn't apply with the NOX.
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  34. I had to pick my wife off at the airport and it's a trip I usually dread but I decided to plan ahead. I threw my metal detector and fishing rod in the car and a lot of water and hit a couple spots along the way or at least in the area. I got my most pieces of silver ever in a single outing and had fun exploring some new water and ground.
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  35. Thanks a bunch GB! I know you weren't looking for the exact spot and I don't share it anyways so no worries but I have no problem giving some tips because people have helped me along the way and if it helps speed up the learning curve and find you some silver I'm happy. I was at a public park and hit the sledding hill on the inclined part not at the top and was using low disc. Field 2 on the Equinox 600. I was actually trying to find nickles which read 12-13, and dug several pull tabs and also botyle caps trying to find gold, and buttons.
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  36. it's common to all detectors. the target moves as the sand/earth is dug.Sometimes the target when a coin moves on edge
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  37. White's 24K is starting to get a little depth now. I just pulled this one at 8" while using the 6" round concentric coil. It is just bigger than my thumb nail and weighs in at 2 grams (30 grains) and was found with the 24K. I still have a few of my initial order not spoken for (at this time). Contact me for details if you are interested in 1.
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  38. Folks have been wanting to see the 24K find small gold. Heck I really don’t care to chase fly shit specs, but I did decide to hunt some ore dump piles for tiny crystal nuggets. No they may not be as small, but before you bark…please know your gold. Crystalline gold does not hit as well as solid pieces and my limited trials with test pieces of small solid pickers does in fact respond louder and farther away than these bits. Yes I am happy with the results of these finds as I had already hunted the exact same pile before, but to be honest it was before I had a manual and now the manual has taught me even more. Contact me if you are interested in the new 24K.
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  39. Jim, Those are very strong and kind words...I'll accept them lightly as I know others on here have put more effort and time sharing their experiences. Yes I have been fortunate with many detectors, but at the same time, I try to put myself in the best situations when trying to make a machine perform. Then there is the skill of the operator behind the detector and I feel years in the field have earned some tidbits of knowledge. Hats off to you for doing something fun that I wish I understood...but in reality it is lack of time. I too am amazed at what a person can do with a rod/probe. I have a good friend in NV who an tell the difference from rusty cans, glass, and hard metal...from rock. He put himself through college digging privies. Last time I witnessed him in action, he pulled about $3K in rare bottles 4 to 6' down. He walks around a site sticking the rod in the ground feeling for the right ting and listen for the right ping. He found this Seven Troughs NEV bottle on that day and had it sold for $900 before he got back home that night.
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  40. OK, I found my camera. Regrettably, I don't take many pictures, but there's enough to get the overall picture. I don't know how many I can load at one time, stick with me though. #1 is the Rokon carrying my frame pack with gear to take down to the river. #2 is our spike camp on the gravel bar #3 is one of my holes on the gravel bar #4 4X4 trying to get down my ATV trail I'll do the rest when I finish the write up on the gold
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  41. I'm a few months into the Equinox by now and growing into it. I think it's a great machine, and I've actually never expected much from it other than the hope that it would give me V3i style multifrequency water operation, so I can go with it where my V3i can't. On land though, I can't say that it's a replacement for the V3i. I'm finding what I'm seeing reported here, that the Equinox is not noticing many targets that the V3i does particularly when they are deeper. I'm finding that it's not quite as deep or as sure of itself as my V3i. There aren't as many tools to rule out junk that my V3i is pretty clear on. It can't be overstated though that I've gone through extraordinary effort to understand the V3i and how to get the most out of it. For the conditions that I deal with I have the V3i dialed right in to where I feel I'm getting the most out of it. I am not yet at that level of confidence with the Equinox that I feel I'm getting every bit of performance it offers, but pretty close. What I can say about the Equinox is that it is even faster than I imagined. I thought that with 200 points of reactivity and the kind of horsepower the V3i has for a processor that it would be able to pretty closely follow the speed of the Equinox if I maxed both out. Not so. Not even close. The Equinox is far quicker Nomatter what I do to the V3i. In heavy trash there's no doubt the Equinox would be my weapon of choice. In harsh ground it would be my weapon of choice. In mild to moderate ground and trash conditions the V3i remains a very powerful coin and jewelry tool. I have noticed that both work best with a conservative sweep speed. Even where the Equinox is maxed out, it is more likely to see those elusive targets if you take your time. Early on I got into a habit of assuming that because of its speed I could swing it at a pretty brisk pace and just investigate when it hit on something. When I began to slow it down a bit it started to see things it hadn't hit on before in the same patch of ground, like a nice buffalo nickel. I'm getting pretty good at sniffing nickels out with it now, usually a solid 13. That's one thing I love about both machines. Once you get to know them, they don't have the trouble with nickels and pull tabs that plague most hunts and most units. Until I got my hands on these two I didnt even consider nickels worth the trouble of chasing. All considered, I feel I have a deadly combo here and I don't think I'd change it. Toward the end of the season when prices of used machines is at the lowest, im going to give the CTX-3030 another go. Other than that I've given all the other machines of note a fair shake. The CTX is the only one I didn't get as much time with as I'd liked to have had. For now, my V3i is still my go-to. There's something about White's machines that agree with Northeastern conditions. They all do very well here. Ill update again later in the season on how these two compare and contrast with more experience on the Equinox.
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  42. I have a friend down in Lake Charles "Tinfoil" has the DFX book and he states it is a winner by far. He is strictly a jewelry hunter and has stated many times the book is right on. Looks like I might need to get a copy and read for my self.
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  43. Well, I will take a stab at it. I surmise Mike has to deal more with foil than tabs? Basically when talking gold and aluminum it is all about size. The larger the aluminum and gold, the higher the target id. Yes, I am simplifying. Smaller jewelry including womens rings tend to fall in the foil range below a U.S. nickel. Larger jewelry like men’s rings tend to fall in the tab area above U.S. nickel. Other than that however in my opinion it’s just something you go try and see what happens. You have to target areas where hands are in motion. You can’t find jewelry unless it’s being lost. Beyond that however there are a host of unpredictable factors, number one these days being the competition. A theoretically great spot may get hunted a lot and so is not good. Some poor locations are actually good because nobody hunts them! The local demographic matters to a huge extent. Probably lots more gold chains lost in Miami than Kansas City for instance. Some places are super trashy. Some places people use trash cans! Put it all together and it is pretty much impossible to put numbers or odds to any of it. I have gone cold to a park and put a ring in my pocket in minutes. Or I can go for long spells digging just aluminum and junk jewelry. Honestly all you can do is give it a good go and see how it works out for you. I find a couple hours of digging aluminum relaxing so no worries. The same couple hours digging aluminum might irritate somebody else. Personality type plays into it a lot, as does a little luck. I hope yours is good luck! Target ID / VDI Numbers For Gold Nuggets And Gold Jewelry Great books to help you out from Clive Clynick at http://www.clivesgoldpage.com/ DFX Gold Methods in particular is a classic. Don’t let the DFX part throw you. The methods described apply to most any detector.
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  44. LIDAR has come a long way since I worked with it in Alaska. I helped build and operate a LIDAR facility while working for the University of California at their remote research site in Fairbanks. Our area of research was ionospheric, we studied the Ionosphere gases for clues to what causes The Northern Lights. We did some ground penetrating work, but it was very limited due to lack of remote receiving sites around the world. Here are some pictures of the LIDAR building in operation and the telescope and laser. The laser light is yellow, which is the color of Sodium. We were studying Sodium at 90 km altitude. The sky is light in this pic because the pic was taken with a long exposure time. This rotating parabolic dish holds 450 lbs of liquid Mercury. It is used as a telescope because there is no distortion like we get in a glass mirror. The dish is 9 feet in diameter.
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  45. Low resolution raw LIDAR data is publicly available for free for about 1/3 of the United States, mostly the east coast and developed areas. High resolution LIDAR (1-3 cm) is available in a few areas. Mostly for environmental studies or only available privately. Without LIDAR we have to rely on DEMs (Digital Elevation Models) for elevation data. These are mostly just a rehash of the old paper topo maps with hand drawn elevation lines converted into even lower resolution digital point shapes represented by light and dark shades on an artificial black and white image. The shades of gray of each pixel represent different elevation values. These DEMs have a high factor of human input error. Mountains and valleys sometimes appear wher there is nothing but a road or a visually confusing feature on the original topo map. If I were to describe the conversion method for these topo's derived DEMs I'm sure you would be in awe of the influence of primitive technology in our "modern" lives. LIDAR is really just a (sometimes) higher resolution version of this system with the difference being the LIDAR points are defined by direct reflection of a laser light rather than ground observations with optical equipment, geometry and trigonometry - traditional survey equipment and methods. The final result in either case is still a grid of values most usually visualized and stored as a photo image in shades of gray. Although just about any data storage format will work humans still naturally understand complex data with their eyes better than any other sense. The features you see on your link were buried in the original LIDAR data. A lot of post processing (number crunching) is necessary to turn the raw data into detail like you see on the website linked. In other words the LIDAR system itself is not discriminating out the trees and ground cover. That is done by applying some pretty complex algorithms to the data after the fact. All of that processing actually lowers resolution and accuracy. To be truly effective for any particular purpose those algorithms are usually customized to the project requirements. We use LIDAR on some of our private mapping projects along with matching high resolution georectified aerial imagery. This can reveal several features you could never see from the ground or the air. We can build 3D models that very closely conform to reality and move through those models in three dimensions. This is a very realistic process and allows us to include measured, extrapolated or even sensed data for underground features. Mining companies love this stuff, not so much for project management but for making presentations for investors. The size of the data involved is a very real problem. Terabytes of data are needed for even a small area and processes take a very long time to run on data that size. Just obtaining the data can be a very long process. We can order a LIDAR scan of just about anywhere in the world but the logistics of producing that scan can be overwhelming. A good high quality scan requires several manned precisely located ground stations as well as some very expensive aerial equipment. Just getting the time booked can be a long wait and getting the skilled ground and air crews working together under ideal conditions can be a virtual impossibility. Add in the difficulty and expense of placing those ground crews on landlocked parcels, hostile territory, difficult terrain or legally challenged access can make the entire process prohibitively expensive and slow. Like much of what is possible in theory the theoretical 1 cm accuracy of a LIDAR scan is rarely if ever achieved in real life. This is not a new technology, it's been around since the 1960's, but until now the technology to push it into the realm of useful and affordable has been lacking. That is changing and I look forward to a time when high resolution ground scans can be considered an accessible tool for many professions. Until then it is a gas to work with small areas in high definition, I only wish more clients could afford the time and money involved in high resolution LIDAR.
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